1590s, "one who shares the same room," from M.Fr. camarade (16c.), from Sp. camarada "chamber mate," originally "chamberful," from L. camera (see camera). In Spanish, a collective noun referring to one's company

When the socialist movement gained momentum in the mid-19th century, socialists began to look for an egalitarian alternative to terms like "Mister", "Miss", or "Missus". They chose "comrade" as their preferred term of address. In German, this practice was started in 1875, with the establishment of the Socialist Workers' Party of Germany.[1][2] In English, the first known use of the word with this meaning was in 1884 in the socialist magazine Justice.